Machine for trimming the edges of panels

ABSTRACT

A machine for trimming the edges of panels wherein a first conveyor mechanism passes the panels past a pair of saws for trimming the side edges of the panels and a second conveyor mechanism passes the panels past a second pair of saws for trimming the end edges of the panels. The machine has transfer mechanism for transferring the panels from the first conveyor system to the second conveyor system. The machine includes a device for severing the web between the panels as they pass through the machine, and includes also a device for turning the panels over when they have been trimmed.

United States Patent Morse et a1.

MACHINE FOR TRIMMING THE EDGES OF PANELS Inventors: Donald B. Morse; Bernard A.

Pribish, both of Joliet, lll.

Assignee: Kemlite Corporation, Joliet, 111.

Filed: Dec. 15, 1972 Appl. No.: 315,494

Related US. Application Data Division of Ser. No. 99,135, Dec. 17, 1970.

US. Cl 83/79, 83/358, 83/360, 83/404.2, 83/408, 83/415, 83/422, 83/425.2, 83/461 Int. Cl B26d l/12, B27b 5/04 Field of Search 83/409, 415, 422, 425.2, 517, 83/404.1, 404.2, 407, 408, 425.3, 435.1, 79, 358, 360, 461

References Cited UNITED STATES PATENTS me Q 3,388,727 6/1968 Kotila 83/409 3,286,744 11/1966 Stall et a1 3,138,179 6/1964 Brettrager 3,538,963 11/1970 Adams 83/415 1,329,634 2/1920 Schumacher et a1. 83/425.2 X 1,700,400 l/l929 Carlson et a1 83/425.2 X 2,022,799 12/1935 Blosser et a1. 83/415 X Primary Examiner-Frank T. Yost Attorney, Agent, or Firm-Carl C. Batz [5 7 ABSTRACT A machine for trimming the edges of panels wherein a first conveyor mechanism passes the panels past a pair of saws for trimming the side edges of the panels and a second conveyor mechanism passes the panels past a second pair of saws for trimming the end edges of the panels. The machine has transfer mechanism for transferring the panels from the first conveyor system to the second conveyor system. The machine includes a device for severing the web between the panels as they pass through the machine, and includes also a device for turning the panels over when they have been trimmed.

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PAIENIEDJANQS \974 SMET 08 0F PATENIEU JAN 29 I974 SHEET 08 0F PAIENIE JMMM $788,174 I saw OBOF 14 so 73 m2 M121 PATENTEDJAN29 I974 SHEET 1 0 BF Z IL 8ll.

MACHINE FOR TRIMMING THE EDGES OF PANELS This application is a division of copending application Ser. No. 99,135, filed Dec. 17, 1970, entitled Machine for Trimming the Edges of Panels.

SUMMARY This invention relates to a machine for trimming the edges of panels. More particularly, the invention relates to a machine which will receive panels such as the common 4 by 6 foot plywood panels, continuously, as they come from a forming machine, and trim and square the panels automatically.

The machine is especially adapted for the treatment of panels of plywood or the like which come from the forming machine with their top surfaces coated with a continuous film of material such as a resin-impregnated fiberglass. The machine may be utilized for the trimming of panels of many-different types, sizes and materials, but for the purposes of detailed description given herein we will describe the machine as it is applied to panels having a continuous coating of resinimpregnated fiberglass.

BACKGROUND A most common form of building material is the panel, such as the well' known plywood panels which come in many convenient sizes, thicknesses and tinishes. One of the problems in the preparation of the panels is to get the edges out straight and square so that the panels can be used where tolerances are not great and to eliminate hand work when the panels are put in place. It is further desirable to accomplish this automatically at a morerapid rate and without hand labor or human attention.

Machines have heretofore been devised for forming the panels and delivering them continuously, but the edges need trimming, and squaring needs to be done to make the edges true and accurately aligned.

We refer particularly to Menzer US. Pat. No. 3,377,228 which describes the formation ofa structural panel wherein a fiberglass mat is impregnated with resin in a continuous manner providing a top layer which is placed on the top surfaces of plywood panels which follow one after the other on a conveyor. The composite panels, with the continuous sheet as a top layer are passed through, a heating zone where the resin is cured, and thepanels are delivered for further finishmg.

In the prior practice such further finishing has required skilled hand labor. The resin coating had to be trimmed all about the edges'of the panel, and this was slowly and laboriously done by a skilled operator using a knife. In order to have the coating extend to the side edge of the panel it was necessary that the coating extend over the edge somewhat, and this had to be trimmed off as well as to sever the web between the panels. In this trimming operation one slip of the knife many times meant that the panel was ruined. Such hand trimming not only was slow and required a great amount of skill but was a very unpleasant task, and it became very difficult indeed to get men who could and would perform the operation.

By this invention we provide a machine which will perform the necessary functions automatically and which will do the job far more accurately than it possibly could be done by hand and at a much greater rate.

THE DRAWINGS One embodiment of the invention is set forth in the accompanying drawings in which FIG. 1 is a top or plan view of the machine;

FIG. 2 is a view of the machine inside elevation;

FIG. 3 is a view of the machine in front elevation;

FIG. 4 is a view of one of the saws in side elevation, taken from the line 4'4 of FIG. 1;

FIG. 5 is a view of the saws and hogger devices in front elevation taken from line 55 of FIG. 1;

FIG. 6 is a detail view of the hogger saw adjustment in front elevation, taken from line 6+6 of FIG. 1;

FIG. 7 is a detail view in side elevation of the saw; the

hogger device and the adjustment linkage taken line 77 of FIG/6;

FIG. 8 is a detail view in side elevation, of the breakup mechanism;

from

FIG. 9 is a detail view in front elevation showing the FIG. '10 is a detail view in side elevation showing the drive chains;

FIG. 11 is a plan view in detail, showing the drive chains, the drive rolls and drive clutches;

FIG. 12 is a detail view in side elevation, showing mechanism for driving the rolls;

FIG. 13 is a sectional view of the carriage, including the hydraulic drive motor;

FIG. 14 is a detail view in side elevation of the carriage, showing the adjustment for different panel widths;

FIG. 15 is a detail view of the carriage panel support adjustment as seen from line .l5l5 of FIG. 13;

FIG. 16 is a plan view in detail of the carriage panel support adjustment as seen from line l6l6 of FIG.

FIG. 17 is a view in elevation of the flipper mechanism taken as seen from line l7-l7 of FIG. 1;

FIG. 18 is a front view in elevation of the flipper mechanism;

FIG. 19 is a side elevational view of the cam lock of the flipper mechanism, the view being taken as seen from the line 19-19 of FIG. 18;

FIG. 20 is a detail view in side elevation of the grippers shown in FIG. 17;

FIG. 21 is a detail view in front elevation of the panel end positioner;

FIG. 22 is a detail view in front elevation of the panel end positioner;

FIG. 23 is a side view in elevation of the panel end positioner in its retracted position;

. FIG. 24 is a side view in elevation of the panel end positioner within the end lip in closed position with the cylinder pistons extended;

FIG. 25 is a detail view of the panel drop adjustment including its carrier and nut;

FIG. 26 is a detail view partly in section showing the panel drop hinge in open position (solid lines) and in closed position (dotted lines);

FIG. 27 is a detail side view of the panel drop adjustment including the carrier and nut;

FIG. 28 is a detail view, partly in section, of the central panel support on the carriage in operated (dotted lines) and non-operated (solid lines) positions;

FIG. 29 is a detail planview of the carrier and the mechanism for squaring the sides of the panels;

FIG. 30 is a circuit diagram showing schematically the switches and the devices they bring into operation;

and

FIG. 31 is a perspective view of the untrimmed panels joined by the resin-impregnated fiberglass web, as they come from the forming machine and are fed to our trimming machine.

GENERAL DESCRIPTION We have now devised a mechine which will automatically saw and square the edges of the panels to be finished, and which in the case of the plywood panels having the top layer of fiberglass-resin, will automatically sever the continuous top layer between the panels.

For convenience of description we will treat the machine as being composed of its principal parts according to their functions. The first sawing mechanism A operates to trim the sides of the panel; then the breakup mechanism B operates to sever the web between one panel and the following panel; the transfer mechanism C serves to transfer the panel to a second conveyor system D; in the system D the panel is squared and passed through a second sawing mechanism; and following the second sawing operation the flipper mechanism E operates to turn over the trimmed sheet in accordance with a predetermined pattern.

FIG. 31 shows the panels as they come from the forming machine with the top reinforced resin layer being continuous, and the plywood panels 171 arranged one after the other with their ends spaced apart so that between the trailing edge 172 of one panel and the leading edge 173 of the next panel is a connecting web 174 of resin-impregnated fiberglass.

As the panels come from the forming machine in the form above described they are fed directly into the front end of our machine where they are first passed through sawing mechanism A which trims the side edges of the panels. As they pass through the saws the webs between the panels remain unbroken and help to hold the panels against turning or twisting.

After a panel has been sawed and passes a certain point beyond the saws a switch is tripped which brings the break-up mechanism B into operation and this severs the web between this panel and the next one. This makes it possible for the panels to move independently from this point on.

As a panel passes beyond the break-up mechanism it comes to be controlled by the transfer mechanism C the function of which is to transfer the panels to a second saw and conveyor system where the ends of the panels are sawed. The mechanism C accomplishes its transferring function by first speeding up the rate at which a panel passes through the machine after it has been severed from the succeeding panel. This serves to separate a forward panel from the others.

The forward panel passes quickly to where it rests on a temporary support and then when it has moved to a certain position it trips a control device which removes the support and allows the panel to fall onto a carriage below.

Associated with the carriage is the mechanism D for squaring and binding the panel with respect to the carriage. With the panel in squared position and bound to the carriage, the carriage moves to carry the panel laterally through the second set of saws to trim the ends of the panel.

After passing the saws for trimming its ends the panel passes into the flipper mechanism E which at first receives the panel, then holds it, then turns it over and finally releases it, so that it may be taken from the machine.

These mechanisms all have drive means and control means for accomplishing their functions as generally described above without effort or direction on the part of an operator. These drive means and control means will later be described in more detail.

The above general description is given for the trimming of panels having a continuous top layer of a material such as resin-impregnated fiberglass such as illustrated in FIG. 31 of the drawings, but the machine may be used for the trimming of panels which are separate and formed of any material capable of being cut or sawed at its edges.

While the machine is intended for trimming large numbers of panels to the same size there is provision for easy adjustment to accommodate different sizes of panels, that is, different widths, and different lengths of panels. Also the machine will accommodate within reasonable limits panels of widely differing thicknesses.

DETAILED DESCRIPTION Mechanism A for Trimming the Side Edges Mechanism A is shown in its relation to the whole machine in FIGS. 1 to 3, and is more specifically shown in FIGS. 4 to 7, with the drive being shown in FIGS. 10 to 12.

This mechanism, as well as the other working parts of the machine, are supported generally in a frame which includes a pair of spaced longitudinal members 1L and IR, and cross members 2L and 2R which are tied at their ends by structural members 5L and SR (The latter L accompanying the character denotes left", and the letter R denotes right"). These frame members may be welded at their junctions and suitably supported by legs (See FIG. 2).

For mounting the saws we have a pair of shafts 15a and 15b which are spaced apart and are held at their ends by the shaft frame structure 153L at the left end and 153R at the right (See FIGS. 5, 6 and 7) which structures rest upon and are secured to the corresponding frame members 1L and IR.

Referring to FIG. 5, two saw assemblies are provided, saw 19L, guarded by the shield 17L and powered by electric motor 13L and saw 19R guarded by shield 17R and powered by motor 13R. The saw assembly which includes saw 19L and motor 13L is carried by the block 10L through which extends the shafts 15a and 15b; and the saw assembly which includes saw 19R; Motor 13R is carried by the block 10R which in like manner receives the shafts 15a and 15b.

A screw adjusting rod 16 is formed of two parts. On the left the part 16a has its left end rotatably mounted in the frame structure 153L and is threaded with the threads advancing from the center toward the left. The part 16b has its right end rotatably mounted in frame structure 153R and is threaded with the threads advancing from the center to the right. Parts and 16b are joined at the center to form a unitary rod.

The left saw assembly has attached to it a nut carrier 12L which is in threaded engagement with part 16a of rod 16 and the right saw assembly has the nut carrier 12R which is in threaded engagement with the part 16b of rod 16. There is provision at one end of shaft 16 for attaching a crank or wrench so that this rod may be rotated in one direction to cause the assemblies to move apart and in the other direction to cause them to move toward each other thus providing means for accommodating panels of different widths. Of course, it is not important which direction the threads on 16a and 16b advance so long as the threads advance in different directions.

It is desirable to provide a device known as a hogger which cooperates with a saw to chew up the material which is sawed off in the trimming operation. We provide such a device which, referring to FIGS. 4 and 5, is designated 14L. This device includes the hogger shoe 20L which operates in association with saw 19L and which is carried by the block 14L. Associated with the saw 19R is a second hogger device 20R which is carried by the block 14R. As shown particularly in FIG. 4, these blocks 14L and 14R contain cylindrical holes through which the spaced guide shafts 14c and 14d extend. Shafts 14c and 14d have their left ends fixed in the frame and serve to stabilize the hogger devices as they are slidably moved along the shafts when adjustments are made.

Near the center of each of blocks 14L and MR is a tapped hole'through which extends a threaded shaft 11 which, like rod 16, has its left-hand part 11a threaded in one direction and its right-hand part 11b threaded in the other direction.

Referring more particularly to FIGS. 6 and 7, the rod and shaft 11 are provided at their left ends with sprockets 16c and 110 respectively,- and the sprockets are connected by the chain 11d.-

The threads on rod 16 and shaft 11 are of the same pitch so when the rod 16 is turned to move the saws closer together or farther apart the hogger devices are correspondingly moved so as to be in the same relationship with their respective saws whatever the width of the panel for which the saws may be adjusted.

For feeding the panels and passing them through the saw mechanism for trimming the side edges of the panel we provide rolls which in the specific construction illustrated include roller members mounted on shafts. As shown more particularly in FIGS. to 12 the first pair of rolls 33 includes the shafts 33a and 33b which are located one above the other. Their left ends are mounted in the bearing 39aL and their right ends are mounted in the bearing 39aR. The bearings are such as to permit upward movement of shaft 33b against spring pressure. Mounted on shafts 33a and 33b are the roller members 36. 7

Similarly, the second pair of rolls 32 include the shafts 32a and 32b which have their ends mounted in bearings 39bL and 39bR and have the roller members 36. Likewise shafts 32a and 32b are adapted to be pressed apart in accordance with the thickness of the material being passed between the rolls. There is, however, one difference in that there is attached to the outside surface of the end roller members on shaft 32a a guide plate 40 which is intended toretain the side edge of the panels and help keep them in alignment.

The wheels or roller members 36 on shafts 33a and 33b are secured to the shafts with set screws and have the guide plates positioned so that the edge of the panel rides on the wheels next to the guides. For convenience a shaft together with its wheels or roller members may be called a roll" and two shafts, such as 33a and 33b, together with their assembled roller members, may be called a pair of rolls.

As shown at the right-hand end of FIGS. 1 and 2 the saws are located between the rolls 33 and 32 so that the panels as they enter the machine pass between the pair of rolls 33, then into the saws, and then between the pair of rolls 32.

In order that the machine be fed at the same speed as panels are delivered to it the power for driving the pairs of rolls 33 and 32 is taken from the same source that drives the forming machine. Power from this source drives the chain 43 (FIGS. 10 and 11) located at the right hand side of the machine. Chain 43 drives sprocket 33d attached to shaft 33a. At its end this shaft is provided with a low inertia clutch 38. The shaft 33a has attached to it a sprocket 33e which drives a chain 42 which drives shaft 32a through sprocket 32d.

At the left side of the machine (See particularly FIGS. 11 and 12) the shaft 33a has attached to it a sprocket 33f which is connected by chain 151 to a sprocket 152 mounted on shaft 154 which is rotatably mounted to the frame member 1L. Above shaft 154 is a shaft 155 similarly mounted, and the gear 156 mounted on shaft 154 is meshed with the gear 157 on shaft 155. The sprocket 158 on shaft 155 connects through chain 45 with the sprocket 159 on shaft 32b. Therefore, the shaft 33a, through appropriate gearing mechanisms drives also the shaft 33b yet allows for the separation of shaft 33b from 33a to allow for the thickness of panels being passed between this pair of rolls.

By similar mechanism and in a similar manner the shaft 32a drives the shaft'32b.

The Break-up Mechanism members on its rear side. Provision is made for raising f or lowering frame 48 with respect to the main frame members 1L and IR and means for doing this will later be explained.

The knife carrier 21 has its left-hand end attached to the cross strap 23L and its right-hand end attached to a similar strap at the right-hand side of the machine. Strap 21 is T-shaped in cross section and attached to its depending portion are a number of knife sections 27 which when attached next to each other provide the knife which is to sever the web between the panels. As shown particularly in FIG. 9a these sections have slanted bottom edges with the tips 27a extending slightly over the next succeeding section.

The anvil carrier 53 has its left-hand end attached to the cross strap 161L and its right-hand end attached to a similar strap at the right-hand side of the machine. The anvil carrier 53 is in the form ofa channel iron and has attached to each side of the channel the anvil bars Referring to FIG. 8, the straps 23 have their left ends provided with bushings which slidably engage guide bar 160a and their right ends have bushings which slid ably engage guide bars 160b. Similar structure is provided at the right-hand side of the machine. Thus, it is clear that the knife carrying structure, and also the anvil carrying structure, may move up and down guided by the bars 160a and l60b at the left-hand side of the machine and by similar bars at the right-hand side of the machine.

For moving the knife carrier and the anvil carrier toward and away from each other, we provide the gear 25L at the left-hand side and gear 25R at the right-hand side. Gear 25L is provided at its center with a pivot piece 56L which is retained in the cross frame member 58L which has its ends attached to bars 160a and 160b. The gear 24R, at the right-hand side of the machine, is similarly provided with a pivot piece which is retained in a cross frame member having its ends attached to bars 160a and 160d.

On its inner side gear 25L is provided with a cam track 164 of the shape illustrated in FIG. 8, and received in this cam track at its uppermost point is the roller 61 which is rotatably mounted at the center of slide strap 23L. Received in the lowermost point of cam track 164 is the roller 165 which is rotatably mounted at the center of strap 161.

Similarly, gear 25R is provided on its inner side with a cam track, and rollers engaging the top and bottom of this track are attached respectively to the right ends of the knife carrier and the anvil carrier.

When gears 25L and 25R are rotated simultaneously by engagement with gears 26L and 26R which are fixed on shafts 59L and 59R. Shafts 59L and 59R have their outer ends rotatably mounted in the frame and at their inner ends are connected with a hydraulic drive device 24 of well-known manufacture which is capable of driving the shafts 360 in one direction and when next operated 360 in the other direction. The gears 25L and 25R each have twice as many teeth as the gears 26L and 26R with which they are engaged, so rotation of gears 26L and 26R through 360 produces rotation of gears 25L and 25R through 180.

Referring more especially to FIG. 8, it may be seen that with roller 61 at the top of the cam track and roller 165 at the bottom of the track, the knife 27 is well separated from the anvil bars 53. However, when the gears 25L and 25R are rotated through 90 the knife will have been brought down and the anvil bars brought up to a position in which the bottom of the knife has passed below the top of the anvil bars and down between them. This means that anything between the knife and the anvil bars will have been severed. Then when the gears 25L and 25R rotate through another 90 the knife and anvil bars will separate and return to their original positions.

The position at which the knife and anvil bars come together may be critical and to raise or lower this position we provide means for raising or lowering the frame 48 with respect to the main frame of the machine.

Referring again to FIGS. 8, 9 and 9a, there is mounted at the four corners of frame 48 the vertical rack pieces 28. The frame 48 is located within the frame members II. and IR, and is guided in its movement vertically with respect to members II. and IR by the rollers 49L which are carried by frame members 166L and 166R fixed respectively to the main frame members 1L and IR.

Rotation of the worm 30a in one direction turns gear 30 in one direction which through gear 29L and 29R and their engagement with racks 28 serve to raise the frame 48 with respect to the main frame, and rotation of worm 30a in the opposite direction, therefore, serves to lower the frame 48 with respect to the main frame.

Such adjustment to raise or lower frame 48 and the knife and anvil carriers within it with respect to the main frame is desirable to accommodate thicker or thinner panels which have as their top layer a continuous sheet of reinforced resin. When the plywood under layer is thicker the web between the panels is raised and it is necessary to raise frame 48 to bring the anvil barsup to the under side of the web between the ends of the plywood as the knife descends to strike and sever the web, and conversely when the plywood layer is thinner it is necessary to lower the frame 48 so that the anvil bars will not strike the web before the knife. The Transfer Mechanism After the web between the panels has been sheared or otherwise severed the next event is to transfer the forward panel to mechanism for squaring the panel and trimming the ends. The first step in the transfer operation takes place when the panel is sent on at a faster rate of speed than the speed at which the other panels are moving so as to separate the forward panel from the others and thus prevent jamb-ups while the positioning and squaring operations are taking place.

Referring again to FIGS. 10 to 12, there is provided a pair of shafts 31a and 31b, with shaft 31b over shaft 31a. Rolls 31 are horizontally aligned with rolls 32 and 33. The end rollers 36 on shafts 31a and 31b, like those on shafts 32a and 32b, are also providedwith the guide flanges 40 on their outer edges, to act as guides for the panels as they pass through rolls'3l.

Shaft 31a is driven by shaft 32a through sprocket 32a, chain 41 and sprocket 312. Shaft 31b is driven by shaft 31a through sprocket 31d, chain 35, and sprocket 31C. The idler sprockets 31fand 31g also engage chain 35 and permit an arfangement whi'haftsia and 31b may separate vertically without binding or disengagement of the drive.

Although shafts 31b and 31a are normally driven, as above described, at the same rateof speed as shafts 31a and 33a, there is provision for'driving them at a greater rate of speed. At its right-hand end shaft 31a is provided with a clutch 37, and at its left-hand end shaft 31a is provided with a motor 34 which is designed to drive the shaft faster than its normal rate with clutch 37 permitting the overdrive. The motor 34 may be hydraulic or electric as may be convenient.

When shaft 31a is driven faster than shafts 32a and 33a the panel then engaged between rolls 31 will be advanced and passed by itself quickly forward within the machine, with its side edges supported by the panel drop supports 76L and 76R.

The support 76R at the right of the machine is a strip extending longitudinal (See FIGS. 1 and 26) and when in support position (dotted lines in FIG. 26) serves to support the right-hand edge portion of the panel. At spaced points along its length this strip is pivotally mounted to the strip 76a which is attached to the frame. At these spaced points the strip 76R has on its 9' under side the levers 167 which are pivotally connected at their ends to the pistons of the fluid cylinders 79.

Thus when the fluid cylinders operate to extend theirv pistons this moves the supporting strip about its pivot into the position shown in dotted lines in FIG. 26 so as to support the side edges of the panel which is passed onto the strip, and conversely when the pistons are retracted, the strip 76R is moved about its pivot to remov'c support of the right side edge portions of the panel.

Similarly, the strip 761. which is spaced from the strip 76R by a distance a bit greater than the width of the panel, extends in like manner and is similarly mounted pivotally with the strip 76b secured to the frame, and spaced cylinders of the same type mounted on strip 76a operate through similar connections to hold strip 76b in support condition when the pistons are extended and to move this strip pivotally when moving to retracted position to remove support for the left side edge portion of the panel.

The cylinders 79 are arranged to operate in unison so that when the forward panel moves to a position where it trips the control both strips 76L and 76R drop down to permit the panel to fall down to the bed of the carriage (See FIGS. 13,- 14, 28 and 29).

The strips 76a are attached to the frame in a manner which will permit adjustment to allow for different width panels. This attachment is illustrated in FIGS. and 27. The ends of the strips 76a are attached to the frame member 77 through the block 80, and the set screws 199 secure the panel drop assembly to the adjustment nut 201.

The strips 76b are attached to the frame in a manner similar to that above described for strips 76a.

The Conveyor System D While the side edges of the panels are supported on strips 76L and 76R the center portion of the panel is supported on the bar 120 (See FIG. 28). This bar is in its upper position, as shown in dotted lines in FIG. 28, being pressed in this position by the fluid cylinders 122a and 122b while the strips 76L and76R are in supporting position. However, when pressure on cylinders 122a and 122b is relieved and the strips 76R fall, the bar 120 also moves down permitting the panel to fall flat on the bed of the carriage. (See FIGS. 13 and 29).

The bed of carriage 170 is formed of the adjustable slats 72L on the left, adjustable slats 72R on the right and stationary slats 72 in the center (See FIG. 29). These slats are supported at their ends on the cross members 3L and 3R, forming a carrier frame which is slidably mounted about shafts 70L and 70R and supported on frame members 2L and 2R by roller members 71L and 71R.

In order that the panel be properly squared it is desirable first to make such that the panel lays flat on the carrier bed and that it is not displaced endwise. We have found that some panels may be slightly warped or in falling to 'the carrier bed become displaced endwise. To correct such irregularities we provide mechanism for pressing the end portions of the panels downwardly and means for positioning the ends of the panel.

Referring now to FIGS. 2, 21, 22, 23 and 24, the presser bar 175L is connected at its center to the piston of cylinder 110L which is mounted on frame member 81L. At its sides are the guides 1l2aL and 112bL which extend upwardly through bushings l76aL and l76bL.

It will be seen that operation of the cylinder l10 L to extend its piston presses the bar 175L downwardly with guides 1l2aL and ll2bL sliding in bushings 176aL and 176bL until the presser bar moves against the end portion of the panel.

Hingedly attached to presser bar 175L is strip 1131. and mounted on the top side of bar 175L are the cylinders 111. Cylinders 111 are arranged so that when their pistons are extended they push the strip 113 about its hinged connection with bar 175L to a position where the strip 113L is at 90 with bar lL. FIG. 23 shows the device in open position with strip 113L moved to open position and with cylinder 1 10L in retracted position. FIG. 24 shows the same device after the cylinder 111 has operated to bring the strip 113L to closed position where it makes with the bar 175L, showing cylinder L in its extended position.

As the bar L descends against the end'portion of the panel the strip 113L is in the position shown in FIG. 23, but as this bar 175L contacts the panel the cylinders 1 11 are operated to move the strip 113L to the position shown in FIG. 24 which serves to bring the end of the panel into proper position.

It is understood that a second bar 175R is disposed over the trailing edge portion of the panel and the cylinder 110R mounted on frame member 81R operates to bring this bar down onto the panel, and another set of cylinders 111 mounted on the bottom of 175R operate to bring the strip 1 13R about its pivot to confine the right-hand end of the panel.

Referring toFIG. 29, the strips 96L and 96R are disposed in spaced relation on the carriage bed. These strips are adjustably secured in cross members 73 as will later be explained and are intended to'be spaced apart such that the side edges of the panels rest upon them. The strip 96R has a backing flange 96Rl which may abut and serve to retain the right-hand side edge of a panel.

The strip 96L also is adjustably secured in cross members 73. Another strip 75 is hingedly connected with strip 96L. The fluid cylinders 78 which are mounted on the under side of strip 96L may be identical to the cylinders 79 of FIG. 26 and have their pistons connected as shown in FIG. 26, so as to move the strip 75 upwardly about its hinged connection to bring it into a plane at right angles with the strip 96L. Thus, when the panel is laying on the bed of the carrier its righthand side edge is retained by the flange 96R], and when the cylinders 78 operate the strip 75 is brought up against the left-hand side edge to bring the panel to a position where its side edges are at 90 withthe direction of the movement of the carrier.

With the sides of the panel made square, and held in squared condition the cylinders 111 operate to open the lip members 113L and 113R at the ends of the panels and cylinders 110L and 110R operate to bring back the bars 175L and 175R to their raised positions, which leaves the carriage free to move laterally to thus undertake the sawing of the end edges.

Mechanism D for Trimming the Ends of the Panels The saw devices which cut the end edges of the panels bear much resemblance to thesaw mechanism A which cuts the side edges of the panels. Referring particularly to FIG. 1, the spaced guide shafts 1011., carried by the frame, support the motor and saw assembly 100L while the spaced shafts 101R, also carried in the frame, supportthe motor and saw assembly 100R. As- 

1. In a machine for trimming the edges of panels, a carriage on which the panel to be trimmed may be received, means for engaging the opposing edges of said panel to square the panel with the carriage, a pair of saws mounted within said machine and spaced apart a distance equal to the intended dimension of said panel, means for pressing said panel against said carriage to flatten the panel against the carriage, said means including a pressure bar which is pressed against the panel, means mounted on said pressure bar for positioning the other opposing edges of the panel, and means for moving said carriage past said saws to thereby trim the other opposing edges of the panel.
 2. A machine as set forth in claim 1 wherein said means for pressing is mounted in the frame of the machine and wherein said carriage is movable with respect to said frame.
 3. A machine as set forth in claim 2 including means for raising said pressure bar to free it from contact with said panel prior to the operation of said means for moving said carriage.
 4. In a machine for trimming the edges of panels, a carriage which is reciprocately movable and which provides a bed on which a panel may be received flat side down with its end edges parallel with the direction of movement of the carriage, a pair of saws mounted within said machine and spaced apart a distance equal to the intended length of said panel, an elongated backing member extending transversely of said carriage at a 90* angle with the direction of movement of said carriage for engaging one side edge of said panel, means engaging the other side edge of said panel to press said one edge against said backing member to grip said panel between said backing member and said means, and means for moving said carriage past said saws while the panel is thus gripped to thereby trim the end edges of the panel.
 5. A machine as set forth in claim 4 wherein said engaging means includes a lip member pivotally mounted in said carriage and movable about its pivot into engagement with said other side edge of the panel.
 6. A machine as set forth in claim 5 including a fluid cylinder for moving said member about its pivot to bring it into engagement with said other side edge.
 7. A machine as set forth in claim 6 including switch means for actuating said cylinder when said panel comes into place on the bed of said carriage.
 8. A machine as set forth in claim 4 including switch means operable when said carriage has moved to a predetermined position where a panel carried thereon is past said saws for releasing said engaging means to free said panel from the grip of said backing member and engaging means.
 9. A machine as set forth in claim 4 including trimming means for trimming said one side edge of the Panel to make said one edge straight before said panel is pressed against said backing member by said engaging means.
 10. A machine as set forth in claim 9 wherein said trimming means includes a saw and conveying means for passing said panel past said saws and onto the bed of said carriage. 